Earthmoving scraper with explosive loading means



Nov. 24, 1970 a. s. COMER, JR., ETA!- 3,541,709

} mn'muovme SCRAPER wiTH EXPLOSIVE LOADING mus Filed April 26. 1968 '5 Sheets-Sheet 1 mvsmons- GLEN s. COMER, JR. LOYAL o. WATTS NOV. 24, 1970 5, 5 CQMER, JR ETAL I 3,541,709 V YEARTHMOVING SCRAPER WITH EXPLOSIVE LOADING 'YMEANS' Fi led A in 26. 1968 I s Sheets-Sheet INVENTORS GLEN s. COMER. JR. LOYAL o- WATTS ATTORNEYS m v w i 1 6 1 f NOV. 24, 1970 5 JR" ETAL 3 5541309 EARTHQOVING SCRAPER WITH EXPLOSIVE LOADING MEANS Filed Aprii 26, 1968 s sheets-sum s mvsu'roas GLEN s COMER an. LOYAI. o. wxm

BY v W, 2.2 w, +4

ATTORNEYS NOV. 24; 1970 C R, JR ETAL I 3,541,709

EARTHMOVING SCRAPER WITH EXPLOSIVE LOADING MEANS Filed April 26, 1968 5 Sheet--$heet INVENTORS' GLEN s. COMER JR.- LOYAL o. wATT ATTORNEYS Nov. 24, 1970 G. S. COMER, JR., HAL

Filed April 26, 1968 5 Sheets-Sheet 5 INVENTOR S GLEN S COMER, JR. LOYAL O. WATTS ATTORNEYS United States Patent 3,541,709 EARTHlVIOVING SCRAPER WITH EXPLOSIVE LOADING MEANS Glen S. Comer, Jr., and Loyal 0. Watts, Peoria, Ill., as-

signors to Caterpillar Tractor Co., Peoria, 111., a corporation of California Filed Apr. 26, 1968, Ser. No. 724,457 Int. Cl. B601) 1/00 US. Cl. 37-4 ABSTRACT OF THE DISCLOSURE Three embodiments of an earthmoving scraper having at least one ripping tooth disposed adjacent an opening in the scraper bowl to loosen material for loading into the bowl and a repetitive explosive device mounted on the tooth to eject explosive products and impel the loosened material into the bowl, thereby permitting self-loading by the scraper.

The operating economics of scrapers are of critical importance because of the vast quantities of earth to be moved by them at many construction sites. Because of this, considerable effort has been expended to minimize loading time and operating expense. Scrapers having selfloading capabilities have become common since they eliminate the need for additional pusher vehicles and reduce loading time in that the scraper may immediately commence loading upon arriving at a borrow pit or other loading site.

Scrapers generally having a cutting edge adjacent an opening of their bowls so that earth or other material is cut and loaded into the bowl by interaction of the cutting edge with the earth. The cutting edge is generally sufficient for rapid self-loading during an initial portion of the loading cycle. However, as loading continues, earth piles up above and behind the cutting edge so that excessive tractive power is required to move additional earth over the cutting edge and force it upwardly and outwardly to fill the bowl. One of the most common prior art solutions to this problem is the provision of an elevator which extends upwardly and rearwardly from the cutting edge. The elevator assists in moving earth away from the cutting edge into the bowl to permit additional earth to enter over the cutting edge with reduced resistance. Elevator scrapers have been found to be effective in permitting self-loading at rapid rates. However, power to operate the elevator must be provided by suitable couplings from a tractor drawing the scraper thereby reducing tractive power for pulling the scraper. The elevator assembly and the power and control couplings with the tractor entail relatively complex mechanical structure which increases capital expense and repair time. Additionally the elevators are susceptible to choking, binding and breakage from interaction with material being loaded into the bowl.

Thus, there remains a need for relatively simple ap paratus permitting self-loading of scrapers. Particularly, there remains a need for such apparatus which effectively moves earth through an opening in the bowl so that additional earth may freely approach the bowl opening and be loaded.

The present invention provides relatively simple and very effective apparatus for fulfilling the above needs. At least one ground engaging member is disposed adjacent an opening in the bowl to engage and loosen material to be loaded thereinto. Explosive means are positioned adjacent the tooth-like member with an exhaust outlet situated so that exhaust gases directed therefrom encounter and impel the loosened material into the bowl.

Additional advantages and objects of the present in- 7 Claims 3,541,709 Patented Nov. 24, 1970 vention are made apparent from the following description having reference to the accompanying drawings.

In the drawings:

FIG. 1 is a side view, in elevation, of one embodiment of an earthmoving scraper incorporating the features of the present invention;

FIG. 2 is an enlarged fragmentary view taken from FIG. 1 to illustrate the manner in which the ripper tooth is supported from the scraper;

FIG. 3 is another enlarged fragmentary view taken from FIG. 1 with parts in section, of the ripper tooth and a repetitive explosive device mounted thereon;

FIG. 4 is a top view of the ripper tooth of FIG. 3 with a fragmentary portion of its support linkage; and

FIGS. 5 and 6 are side views, in elevation, of alternate embodiments of earthmoving scrapers according to the present invention.

Referring now to FIG. 1, an earthmoving scraper has a bowl assembly 11 partially formed by side walls, one of which is shown at 12, and a floor member 13. The scraper bowl is rearwardly supported by a pair of wheels, one of which is shown at 14. A draft arm 16 is pivotally connected to each bowl side wall as at 17 and extends forwardly for attachment to a transverse draft tube 18. The draft tube is supported by a gooseneck member 19 which is pivotally connected to a suitable hitch 21 on a tractor 22. The scraper bowl has a cutting edge 23 disposed along the forward edge of its floor member 13 for cutting and loading material into the bowl as well as for leveling material ejected from the bowl. An apron 24 is pivotally connected to each bowl side wall as at 26 and is disposed at the forward open end of the bowl. The position of the apron is regulated by a hydraulically actuated member 27. When the apron is lowered against the cutting edge as illustrated in its position 24, it closes the forward end of the bowl and retains loaded material in the bowl, for example, during transportation to a suitable unloading site. During loading or unloading of the scraper bowl, the apron is raised to a posititon 24 illustrated in broken lines, to provide an opening at the forward end of the bowl above its cutting edge. The bowl further includes a hydraulically actuated ejector 28 for unloading material. The bowl assembly is raised or lowered to position it at a suitable height for loading, unloading or transport by a pair of hydraulic jacks, one of which is indicated at 29, connected between the gooseneck member 19 and a spreader member 31 disposed across the forward end of the bowl assembly.

The scraper as described above is of a generally conventional type wherein material has heretofore been loaded into the bowl according to interaction of the cutting edge 23 with the ground and the forward motion of the scraper. With such a scraper, it has been found uneconomical to provide sufficient power in the tractor to permit self-loading of the scraper without the use of a pusher vehicle (not shown).

To adapt the scraper for self-loading according to the present invention, a ripper tooth 32 of conventional wedge-shaped construction, at least in its forward portion, is suspended by suitable linkage 33 from the bowl assembly for disposition forward of the cutting edge 23. When the scraper bowl is lowered into its normal loading position, the ripper tooth 32 is also lowered so that it engages and loosens the earth to facilitate its loading into the bowl. Even with this means of loosening the earth, it is stacked up in the opening of the bowl in front of and above the cutting edge and providing considerable resistance to continued loading of the bowl.

To overcome this problem and permit the scraper to completely load the bowl in a self-loading manner, a repetitive explosive device 34 is situated on a rearward portion of the ripper tooth 32 and has an exhaust outlet (indicated at 36 in FIG. 3) which is rearwardly facing so that explosive products directed from the outlet contact the earth loosened by the tooth and impel it up and over the cutting edge 23 to facilitate loading of the bowl. In this manner, the explosive gases particularly assist in moving the earth out of the bowl opening to substantially reduce resistance to continued loading. Since the earth is being impelled upwardly into the bowl, a cover 37 is provided over the bowl to maintain all of the loaded earth therein. Although the forward end of the bowl is normally open, the apron upon being raised to its loading position 24, cooperates with the bowl cover 37 to completely enclose the upper portions of the bowl during loading.

Having particular reference to FIGS. 2 and 4, the linkage 33 is of an adjustable parallelogram type so that the ripper tooth may be positioned at various elevations relative to the cutting edge 23 according to the characteristics of the earth to be loaded into the scraper. The ripper tooth is rigidly secured to an upwardly extending bracket 38 which is pivotally connected to a pair of lower draft links 39 by a pin 41 and a pair of upper draft links, one of which is indicated at 42, by another pin 43. The lower and upper draft links are respectively connected to another forward bracket 44 by pins 46 and 47. The forward bracket 44 extends upwardly and is secured to the rigid spreader member 31. To vary the elevation at which the ripper tooth is supported by the linkage 33, a hydraulic jack 48 is pivotally secured to a tab 49 upon the spreader member while its rod 51 is pivotally secured to the upright bracket 38 by means of the pin 43.

The explosive device 34 may be of any type for ex pelling gaseous products to act upon earth loosened by the ripper tooth and impel it through the bowl opening to assist in loading of the bowl. The explosive device offers an additional advantage because of its mounting upon the ripper tooth. The rearward expulsion of gas results in a forward reaction force which is transferred to the ripper tooth. Since there will inherently be some play or looseness in the interconnecting linkage 33 which supports the ripper tooth, the repetitive forward reaction forces tend to cause vibration in the ripper tooth which facilitates its penetration of the earth during loading of the scraper.

A typical repetitive explosive device for accomplishing the purposes of the present invention is illustrated in detail at 34 in FIG. 3. A combustion chamber 61 is communicated with the exhaust outlet 36 by means of an exhaust passage 62. There is free communication between the combustion chamber 61 and the passage 62 to permit equalization of pressure thereacross. However, the exhaust passage 62 is normally isolated from the exhaust outlet 36 by means of a valve 63. A valve stem 64 extends upwardly from the exhaust valve 63 through a piston chamber 66 in communication with the exhaust passage 62 and into a spring chamber 67. A spring 68 acts upon the valve stem tending to urge the exhaust valve 63 into a closed position to permit proper charging of the combustion chamber 61 and exhaust passage 62. Combustible reactants such as air and a hydrocarbon fuel are blended in an appropriate ratio for combustion and introduced under pressure (from a source not shown) into the combustion chamber 61 by means of an inlet 69. This pressurization of the combustion chamber and exhaust passage tend to urge the exhaust valve 63 into an open position. However, a piston 71 having a greater crosssectional area than the valve 63 is secured to the valve stem within the piston chamber 66. Pressure existing within the exhaust passage 62 is communicated into the piston chamber 66 and also acts against the larger piston so that the exhaust valve remains closed during charging of the combustion chamber. Suitable detonation means such as a spark plug 72 is disposed within the combustion chamber to initiate explosion of the fuel and air under pressure within the device. Suitable timing means (not shown) provides an intermittent electrical discharge across the spark plug to achieve proper detonation. After the spark plug is actuated and combustion is initiated in the chamber 61, increased pressure from the chamber 61 is communicated to the piston chamber 66 through conduits 73 and 74 to urge the piston downwardly and open the exhaust valve. Communication between the combustion chamber 61 and the piston chamber 66 through the conduits 73 and 74 is regulated by appropriate valve means 76. A timing device (not shown) opens the valve 76 very shortly after detonation of the spark plug to open the exhaust valve 63 for maximum exhaust pressure through the exhaust outlet 36. The valve 76 is automatically closed after an appropriate interval of time so that the combustion chamber 61 may be again charged with a combustible fuel mix with the exhaust valve 63 closed to commence a new detonation cycle. Such repetitive explosive devices are well known in the prior art and have been found to economically provide considerable quantities of energy. Thus the present invention provides simple apparatus utilizing such repetitive bursts of exhaust energy to facilitate loading of the scraper bowl with material suitably loosened by the ripper tooth.

Although the above embodiment has been described with only one ripper tooth and one explosive device to assist in loading, additional similar explosive devices and/ or ripper teeth may be desirable to achieve an optimum loading rate. For this purpose, a plurality of the ripper teeth could be transverely arranged forward of the cutting edge and mounted on the same beam so that the elevation of the teeth could be commonly adjusted by a single parallelogram linkage such as that indicated at 33 in FIGS. 1 and 2.

An alternate embodiment of the invention is illustrated in FIG. 5 and has at least one ground engaging member 80 and a repetitive explosive device 81 supported by a shank or mold board 82. The shank 82 is secured to a parallelogram type linkage 83 so that its elevation is adjustable by means of the hydraulic jack 84. The explosive device 81 is mounted with its exhaust outlet facing generally forwardly so that its exhaust gases act upon earth loosened by the ground engaging member to impel it generally upwardly and forwardly into the bowl through a rearward opening described immediately below.

The scraper bowl 86 is generally enclosed and has an ejector 87 forming the rearward wall of the bowl. The upper end of the ejector is supported by a roller 88 riding in a track 89 formed in each bowl sidewall 91. A lower portion 92 of the ejector is pivoted at 93 and is attached to a hydraulic jack 94 which operates the ejector. After the ejector comes into contact with a stop 96, additional retraction of the jack 94 pivots the lower ejector portion 92 rearwardly to partially form an opening for loading of the bowl by means of the explosive device 81 and ground engaging member 80. After the bowl is loaded, the lower ejector portion 92 is pivoted forwardly by extension of the jack 94 to a position 92, shown in broken lines, established by contact between stop blocks 97. To further enlarge the opening at the rear of the bowl and to assist in directing earth or other material into the bowl, a rearward portion 99 of the bowl floor is pivotable downwardly from its normal position 99' (shown in broken lines) by means of a hydraulic jack 101 mounted on each bowl side wall and connected to the pivotable floor section 99 by means of a bellcrank lever 102 and a link 103.

The scraper has a generally conventional apron 104 which normally abuts a cutting edge 106 at the forward edge of the bowl floor 98 to close the front of the scraper bowl. The apron is raised to open the forward end of the bowl by means of a hydraulic jack which is indicated at 107 and is connected to the apron through a lever 108 and a link 109. The ejector is then operated in a generally conventional manner by extension of the hydraulic jack 94 to eject material from the forward end of the bowl over the cutting edge 106 in a conventional and wellknown manner. With this arrangement, the earthmoving scraper of FIG. 5 permits conventional scraper loading through the forward end of the bowl over the cutting edge 106 for example when very loose material is being loaded and the explosive device 81 is not required to assist in loading.

A structurally simplified embodiment of an earthmoving scraper according to the present invention is illustrated in FIG. 6 with a generally enclosed and unitized bowl structure 111 having a floor assembly 112 pivoted at 113 to each bowl side wall 114. The flood assembly 112 is connected through a lever 116 on each side of the bowl to hydraulic jacks, one shown at 117, which is operable to position the bowl floor for transport, for loading (in the position shown in the drawing) or for unloading the bowl. Usually for unloading of the bowl, the floor is pivoted completely forwardly to permit unrestricted passage of material out of the bowl. After loading, the bowl floor is pivoted rearwardly into contact with a rearward bowl wall 118 to completely close the bowl and retain material during transport.

To load the bowl with the bowl floor in the position shown, at least one ground engaging member 119 is supported rearwardly of the bowl by means of a mold board 121 which is supported by parallelogram linkage 122 to permit raising and lowering of ground engaging member 119 by means of a hydraulic jack 123. A repetitive explosive device 124 generally similar to the one shown at 81 in FIG. 5 and at 34 in FIG. 1, is mounted upon the ground engaging member 119. The explosive device 124 is positioned to have a forwardly facing exhaust outlet so that its exhaust gases act upon earth loosened by the ground engaging member 119 and impel it generally upwardly and forwardly into the scraper bowl. The rearward edge 126 of the bowl floor is generally in contact with the ground to assist in directing material toward the bowl interior. In this arrangement, it is desir-' able to provide a strike-off blade behind the bowl to level material ejected from the bowl. With a plurality of the ground engaging members 119, this could most readily be accomplished in the structure of the ground engaging members or explosive devices 124 particularly since they are already positioned at the rear of the bowl and their elevation can be varied by means of the jack 123.

Although three embodiments of an earthmoving scraper according to the present invention have been described, it is obvious that numerous variations and modifications of the design would be possible within the scope of the present invention. For example, the general scraper configuration shown in FIG. 1 could also be employed with the apron 24, the ground engaging member 32 and the explosive device 34 positioned at the rear of the bowl with the push-type ejector 28 or any other suitable ejector mechanism mounted in the forward end of the bowl.

What is claimed is:

1. An earthmoving scraper having a bowl adapted to provide an opening toward the base of the bowl during loading of earth into the bowl interior, the scraper including at least one tooth member adjustably suspended from the scraper to penetrate and loosen earth to be loaded into the bowl, a repetitive explosive device suspended from the scraper adjacent the tooth member, the device having an exhaust outlet facing generally upwardly and toward the bowl opening during loading so that exhaust gases from the outlet encounter the earth loosened by the tooth member and impel the earth through the bowl opening and toward the top of the bowl interior, the bowl also having a cover for generally enclosing the bowl interior and containing therein the earth impelled upwardly by the explosive device, the scraper bowl being open at its forward end during loading, the tooth member being disposed forwardly of the bowl and the explosive device being mounted on the tooth member with its exhaust outlet facing generally rearwardly and upwardly toward the bowl opening during loading.

2. The invention of claim 1 wherein the tooth member is mounted on the scraper by means of parallelogram linkage for adjusting its elevation relative to the bowl.

3. An earthmoving scraper having a bowl adapted to provide an opening toward the base of the bowl during loading of earth into the bowl interior, the scraper including at least one tooth member adjustably suspended from the scraper to penetrate and loosen earth to be loaded into the bowl, a repetitive explosive device mounted upon the tooth member, the device having an exhaust outlet facing generally upwardly and toward the bowl opening during loading so that exhaust gases from the outlet encounter the earth loosened by the tooth member and impel the earth through the bowl opening and toward the top of the bowl interior, the bowl also having a cover for generally enclosing the bowl interior and containing therein the earth impelled upwardly by the explosive device.

4. An earthmoving scraper having a bowl adapted to provide an opening toward the base of the bowl during loading of earth into the bowl interior, the scraper including at least one tooth member adjustably suspended from the scraper to penetrate and loosen earth to be loaded into the bowl, a repetitive explosive device suspended from the scraper adjacent the tooth member, the device having an exhaust outlet facing generally upwardly and toward the bowl opening during loading so that exhaust gases from the outlet encounter the earth loosened by the tooth member and impel the earth through the bowl opening and toward the top of the bowl interior, the bowl also having a cover for generally enclosing the bowl interior and containing therein the earth impelled upwardly by the explosive device, the opening being provided at the rearward end of the bowl during loading, the tooth member being arranged rearwardly of the bowl opening during loading with the exhaust outlet of the explosive device facing generally upwardly and forwardly toward the bowl opening during loading.

5. The invention of claim 4 wherein the scraper bowl has a rear wall and a movably supported floor with means interconnected between the bowl and floor for moving the floor forwardly during loading to provide the rearward bowl opening.

6. The invention of claim 4 wherein the bowl has a front wall formed by a movable apron and a transverse blade depending from the forward edge of the floor adjacent the movable apron.

7. The invention of claim 6 wherein a rear wall of the bowl is formed by an ejector plate with means for moving the ejector plate longitudinally through the bowl interior, a lower portion of the ejector being pivotable to form the rearward bowl opening during loading of the bowl by the explosive device.

References Cited UNITED STATES PATENTS 2,101,400 12/1937 Lawler 37-28 2,288,701 7/1942 Heden 37-55 3,032,903 5/1962 Ede 37-193 3,092,919 6/ 1963 Reynolds et a1.

3,184,866 5/1965 McMillin 37-55 3,283,426 11/1966 Payne 37-141 3,341,253 9/1967 Hostetter 37-193 X 3,461,577 8/1969 Clark et a1. 299-13 X 3,451,149 6/1969 Munsch 37118 X ROBERT E. PULFREY, Primary Examiner E. H. EICKHOLT, Assistant Examiner U.S. Cl. X.R. 

